Neither did the god of the OT, in the OT.
Oh, I think He did. The Son just was not incarnated yet. But in due time, He came and was invested in a little particle of flesh in the virgin by the Holy Ghost, and grew in Mary's womb; arriving in this world in the completed form of a little human infant.
His title, though known by The Persons of The Godhead from before Creation, was announced to humans through Isaiah:
"Therefore Adonai Himself shall give you a sign; Behold, the Virgin shall conceive, and bear Son, and shall title Him "Immanuel" (Isa 7:14, cf Mt 1:23)
Here the construction of this phrase is that "Son" is anarthrous, therefore it is not merely His relatioship to Father--no, it is His Name!
His name is not only "Son," it is also "Redeemer" when He talks about Himself:
"Come ye near unto Me, hear ye this; I have not spoken in secret from the beginning; from the time that it was, there am I: and now the Lord GOD, and his Spirit, hath sent Me.
Thus saith the LORD, thy Redeemer, the Holy One of Israel; I am the LORD thy God which teacheth thee to profit, which leadeth thee by the way that thou shouldest go." (Isa 48:16-27)
Allah cannot say these things, for he is not the God of the Bible. These Muslim claim to be of Ishmael's descent, so they pick through the Bible to find things that please them, but reject the things that do not. But in that Bible, God says he hates sodomy, and demonstrates his rejection of it. And the Muslims are right in that. Throughout the Bible, sodomy is a capital offense.
"Know ye not that the unrighteous shall not inherit the kingdom of God? Be not deceived: neither fornicators, nor idolaters, nor adulterers, nor effeminate, nor abusers of themselves with mankind, Nor thieves, nor covetous, nor drunkards, nor revilers, nor extortioners, shall inherit the kingdom of God" (1 Co 6:9-10).